1. Field of the Invention
The present invention relates to an exterior structure around a photographing lens barrel portion in a camera, a lens barrel and a method for assembling the lens barrel, and a mounting structure of a printed-circuit board incorporated in an electric device of the camera.
2. Related Art Statement
Japanese Unexamined Patent Application Publication No. 7-20549 discloses a conventional camera body supporting structure of a camera, having the structure of a camera body formed by attaching a front-plate unit, a shutter unit, and a main body unit to a B plate unit from a rear-surface side and by attaching a lens barrel unit from a front-surface side. In the above-mentioned camera, a rear cover as an exterior member is attached to the camera body from the rear-surface side and, further, a cover unit is attached from the front-surface side.
However, a barrel cover portion in the cover unit in the camera disclosed in Japanese Unexamined Patent Application Publication No. 7-20549 needs a taper for pulling out a mold and, when the length of the lens barrel unit is long, the base portion of the barrel cover portion in the cover unit is made thick, thereby causing the limitation on design.
Then, by adopting an exterior structure for inserting a metal cylindrical member into the barrel cover portion with the taper for pulling out the mold, a space is generated at the edge of the metal cylindrical member, the attachment is difficult, and the diameter of the metal cylindrical member is increased. Although the barrel cover portion without the taper for pulling out the mold can be produced, unpreferably, the molding is complicated and a parting line is generated on the surface.
Further, upon attaching the metal cylindrical member, unpreferably on design, a fixed portion is exposed. Furthermore, upon attaching no metal cylindrical member, the management of parts is complicated because the cover unit having a model name must be exchanged in association with the change in assembled camera model.
In a conventional method for adjusting a lens of a lens barrel having a plurality of lens groups, the blur phenomenon on the periphery is suppressed by reducing an optical eccentricity among the lens groups (center deviation of the lens groups) when the spot adjustment (lens center adjustment) between the plurality of lenses are adjusted by a center adjusting device. Further, advantageously, the MTF performance with the telecentricity as center is improved.
On the other hand, when the spot adjustment between the lens groups is not performed, the center matching is executed by an assembling tool. However, in this case, only the center is adjusted between holding frames for holding the lens groups but the optical center matching of the lens groups is not executed. Therefore, the optical performance is not sufficiently obtained.
Upon adopting the method for adjusting the lenses by the spot adjustment among the lens groups using the conventional center adjusting device, the spot adjustment is performed between a pair of lens groups arranged to individual frame members (holding frame and lens-group frame) and, thereafter, the lens groups are fixed to the holding frames by an adhesive. In assembling processing after that, the combination of the pair of lens groups must be controlled so as to prevent the change thereof. Further, the control operation is troublesome because the combination of the lens groups is not visually identified.
Recent cameras require the high quality and the reduction in size. Therefore, on camera design, a method for reducing the size is utilized by enclosing parts such as a printed-circuit board by the effective use of a dead space.
Japanese Unexamined Patent Application Publication No. 7-294790 discloses one of the above-mentioned mounting structures of the printed-circuit board. That is, referring to FIGS. 38A and 38B, in the mounting structure disclosed in Japanese Unexamined Patent Application Publication No. 7-294790, six printed-circuit boards 151a to 151f are combined hexagonally. The six hexagonally combined printed-circuit boards 151a to 151f are accommodated and arranged in a space portion 152a as a ring shaped dead space formed in a lens barrel 152.
However, the conventional mounting structure of the printed-circuit boards 151a to 151f are not sufficient in views of a mounting area (planar area) for mounting an electric part and the small size of the arrangement space (space portion) 152a needs to be ensured and the large mounting area is further required. In particular, the recent variation of camera specifications causes the addition of functions using an electronic device and, consequently, the camera has a pressing problem that the reduction in size of camera body is assured and the mounting area (planar area) of the printed-circuit boards can be increased.
The above-mentioned situations apply not only to the camera but also to various electric devices including optical devices having the printed-circuit board.
The conventional electric devices have a problem that the increase in mounting area of the printed-circuit boards results in the growing in size thereof.
Further, a cam groove diagonal to the optical axis is formed to a cylindrical frame member as means for controlling the linear movement of the frame member, and a cam follower is slidably engaged with the cam groove, thus linearly moving the frame member. In a barrel device using the cam groove, the frame member is molded by using a molding tool and, consequently, the manufacturing is inexpensive in costs.
In the conventional barrel device, the cam groove of the frame member is formed by inclining the opening of the cam groove of the frame member at a predetermined angle so as to prevent an under-position thereof, in consideration of pulling out a projecting portion of the mold from the cam groove. Thus, the mold is pulled out from the product.
There is a danger that the cam follower drops off from the cam groove by applying unnecessary external force such as shock or fall in the assembling state in which the cam follower is slidably inserted in the cam groove of the frame member.